1. The Field of the Invention
The field of the invention relates to an improved deck washer transfer apparatus and method for automatically installing a deck washer onto a deck.
2. Description of the Prior Art
Deck washer transfer means and methods are incorporated in a class of devices known as automatic deck fasteners. These are useful in the installation of deck insulation and/or membrane for example on a roof. A portable driving device feeds a deck screw through a deck washer to fasten it to a deck for the purpose of holding the insulation and/or membrane down. Typical of the art is the device of U.S. Pat. No. 4,657,167 (hereafter '167) to Mays, April, 1987. See also British Patent GB2,181,081 A (hereafter GB'081); U.S. Pat. No. 4,246,939 (hereafter '939) to Boegel, January, 1981 and pending application Ser. No. 161,980 (Feb. 29, 1988; by Zahn). Each discloses, in conjunction with the driving apparatus means for transferring an apertured deck washer from a storage magazine to a position which aligns the aperture with a deck fastener screw's longitudinal axis for installation.
'939 discloses a sliding fixture which contains a defined slot in the pattern of a washer perimeter (FIG. 17 and 18) in combination with free fall. '167 discloses a pivot in a horizontal axis transfer by defined sloted fixture combination with free fall, see also GB'081, as does the Zahn application.
In operation each of the foregoing deck transfer means fails or jams from time to time by virtue of irregularities in washer shape, uncoordinated pivot or sliding motion, free fall misposition and nonalignment of the washer aperture with the deck screw longitudinal axis. Each requires a special defined fixture in the transfer mechanism depending on washer configuration which in the market place, is variable to a great degree. For example, deck washers are known which are round, hexagonal, square, oblong, oblong rounded and oval.